U.S. patent application number 17/607260 was filed with the patent office on 2022-07-28 for environmental equipment and power generation system using same.
The applicant listed for this patent is GEESCO CO.,LTD.. Invention is credited to Sung Ho HONG, Dae Woo KIM.
Application Number | 20220234003 17/607260 |
Document ID | / |
Family ID | 1000006319015 |
Filed Date | 2022-07-28 |
United States Patent
Application |
20220234003 |
Kind Code |
A1 |
HONG; Sung Ho ; et
al. |
July 28, 2022 |
ENVIRONMENTAL EQUIPMENT AND POWER GENERATION SYSTEM USING SAME
Abstract
The present invention provides environmental equipment which is
able to remarkably reduce operating costs and a power generation
system comprising same, comprising: a boiler; a power generation
unit for generating electricity by steam generated from the boiler;
first denitrifying equipment to which exhaust gas is delivered from
the boiler and which sprays a reducing agent into the exhaust gas
to denitrify the exhaust gas; a low-low temperature electrostatic
precipitator for collecting dust of the exhaust gas provided from
the first denitrifying equipment; second denitrifying equipment
which sprays a reducing agent into the exhaust gas provided from
the low-low temperature electrostatic precipitator to secondarily
denitrify the exhaust gas and allows the exhaust gas to be provided
towards a smokestack.
Inventors: |
HONG; Sung Ho; (Seoul,
KR) ; KIM; Dae Woo; (Incheon, KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GEESCO CO.,LTD. |
Yongin |
|
KR |
|
|
Family ID: |
1000006319015 |
Appl. No.: |
17/607260 |
Filed: |
February 18, 2020 |
PCT Filed: |
February 18, 2020 |
PCT NO: |
PCT/KR2020/002288 |
371 Date: |
October 28, 2021 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01D 53/8631 20130101;
B01D 53/75 20130101; B01D 53/96 20130101; B01D 2257/404 20130101;
B01D 53/90 20130101; B01D 2258/0283 20130101 |
International
Class: |
B01D 53/96 20060101
B01D053/96; B01D 53/90 20060101 B01D053/90; B01D 53/86 20060101
B01D053/86; B01D 53/75 20060101 B01D053/75 |
Foreign Application Data
Date |
Code |
Application Number |
May 9, 2019 |
KR |
10-2019-0054542 |
Claims
1. A power generation system comprising: a boiler; an electric
generator which produces electricity based on steam generated in
the boiler; a first denitrifier which receives exhaust gas from the
boiler and denitrifies the exhaust gas by spraying a reductant to
the exhaust gas; a low low-temperature electric precipitator which
collects dust from the exhaust gas provided from the first
denitrifier; a second denitrifier which secondarily denitrifies the
exhaust gas by spraying the reductant to the exhaust gas provided
from the low low-temperature electric precipitator and provides the
exhaust gas toward a chimney; a first heat exchanger which is
provided between the first denitrifier and the low low-temperature
electric precipitator and cools the exhaust gas provided to the low
low-temperature electric precipitator; and a second heat exchanger
which is connected to the first heat exchanger between the low
low-temperature electric precipitator and the second denitrifier
and heats the exhaust gas provided to the second denitrifier.
2. The power generation system of claim 1, wherein the second
denitrifier secondarily denitrifies the exhaust gas based on a low
temperature selective catalytic reduction (SCR).
3. The power generation system of claim 1, wherein the first heat
exchanger cools the exhaust gas, to be provided to the low
low-temperature electric precipitator, to have a temperature of
80.about.100 degrees, and the second heat exchanger heats the
exhaust gas, to be provided to the second denitrifier, to have a
temperature of 150.about.200 degrees.
4. The power generation system of claim 1, further comprising: a
third heat exchanger which is provided between the second
denitrifier and the chimney and cools the exhaust gas to be
provided to the chimney; and a fourth heat exchanger which is
connected to the third heat exchanger and heats air to be provided
to the boiler and used for combustion.
5. The power generation system of claim 1, further comprising a
catalyst regenerator which is connected to at least one of the
first denitrifier and the second denitrifier and supplies a
catalyst regeneration material toward a catalyst in the
denitrifier.
6. The power generation system of claim 5, wherein the catalyst
regenerator sprays dry ice toward the catalyst.
7. The power generation system of claim 5, wherein the catalyst
regenerator alternately sprays dry ice and hot steam toward the
catalyst.
8. The power generation system of claim 5, wherein the catalyst
regenerator comprises: a sprayer which is provided outside the
denitrifier and supplies the catalyst regeneration material from
the outside, and a spraying nozzle which is extended from the
sprayer to an inside of the denitrifier and moves up and down
inside the denitrifier by a motive power source to spray the
catalyst regeneration material toward the catalyst.
9. The power generation system of claim 5, wherein the catalyst
regenerator sprays the catalyst regeneration material to the
catalyst when the catalyst is poisoned.
10. Environmental equipment connected to a boiler of a power
generation system, comprising: an electric generator which produces
electricity based on steam generated in the boiler; a first
denitrifier which receives exhaust gas from the boiler and
denitrifies the exhaust gas by spraying a reductant to the exhaust
gas; a low low-temperature electric precipitator which collects
dust from the exhaust gas provided from the first denitrifier; a
second denitrifier which secondarily denitrifies the exhaust gas by
spraying the reductant to the exhaust gas provided from the low
low-temperature electric precipitator and provides the exhaust gas
toward a chimney; a first heat exchanger which is provided between
the first denitrifier and the low low-temperature electric
precipitator and cools the exhaust gas provided to the low
low-temperature electric precipitator; and a second heat exchanger
which is connected to the first heat exchanger between the low
low-temperature electric precipitator and the second denitrifier
and heats the exhaust gas provided to the second denitrifier.
11. The environmental equipment of claim 10, wherein the second
denitrifier secondarily denitrifies the exhaust gas based on a low
temperature selective catalytic reduction (SCR).
12. The environmental equipment of claim 10, wherein the first heat
exchanger cools the exhaust gas, to be provided to the low
low-temperature electric precipitator, to have a temperature of
80.about.100 degrees, and the second heat exchanger heats the
exhaust gas, to be provided to the second denitrifier, to have a
temperature of 150.about.200 degrees.
13. The environmental equipment of claim 10, further comprising: a
third heat exchanger which is provided between the second
denitrifier and the chimney and cools the exhaust gas to be
provided to the chimney; and a fourth heat exchanger which is
connected to the third heat exchanger and heats air to be provided
to the boiler and used for combustion.
14. The environmental equipment of claim 10, wherein further
comprising a catalyst regenerator which is connected to at least
one of the first denitrifier and the second denitrifier and
supplies a catalyst regeneration material toward a catalyst in the
denitrifier.
15. The environmental equipment of claim 14, wherein the catalyst
regenerator sprays dry ice toward the catalyst.
16. The environmental equipment of claim 14, wherein the catalyst
regenerator alternately sprays dry ice and hot steam toward the
catalyst.
17. The environmental equipment of claim 14, wherein the catalyst
regenerator comprises: a sprayer which is provided outside the
denitrifier and supplies the catalyst regeneration material from
the outside, and a spraying nozzle which is extended from the
sprayer to an inside of the denitrifier and moves up and down
inside the denitrifier by a motive power source to spray the
catalyst regeneration material toward the catalyst.
18. The environmental equipment of claim 14, wherein the catalyst
regenerator sprays the catalyst regeneration material to the
catalyst when the catalyst is poisoned.
19. A power generation system comprising: a boiler; an electric
generator which produces electricity based on steam generated in
the boiler; a low low-temperature electric precipitator which
receives exhaust gas from the boiler and collects dust from the
exhaust gas; a denitrifier which denitrifies the exhaust gas by
spraying the reductant to the exhaust gas provided from the low
low-temperature electric precipitator and provides the exhaust gas
toward a chimney; a first heat exchanger which is provided between
the electric generator and the low low-temperature electric
precipitator and cools the exhaust gas provided to the low
low-temperature electric precipitator; and a second heat exchanger
which is connected to the first heat exchanger between the low
low-temperature electric precipitator and the denitrifier and heats
the exhaust gas provided to the denitrifier.
20. (canceled)
Description
TECHNICAL FIELD
[0001] The disclosure relates to environmental equipment and a
power generation system including the same, and more particularly
to environmental equipment for reducing discharge of pollutants and
a power generation system including the same.
BACKGROUND ART
[0002] Numerous thermoelectric power plants generally operate based
on coal or petroleum. In particular, with recently tightened
regulations on environmental pollution, environmental equipment
capable of reducing discharge of pollutants has been increasingly
researched, developed and spread.
[0003] The related art of such environmental equipment has already
been disclosed in Korean Patent Publication No. 2017-0142377
(titled "POLLUTANT REMOVAL APPARATUS AND COMBINED CYCLE POWER
GENERATION SYSTEM" and published on Dec. 28, 2017). This related
art is characterized in the pollutant removal apparatus that
reduces pollutants generated from the thermoelectric power
plants.
[0004] However, acceptable pollutant-discharge standards are
tightened, and thus high-efficiency technology of using a
denitrifying catalyst is required to reduce nitrogen oxide, i.e., a
precursor of fine dust, which has come up as an environmental
issue, into a few PPM levels. Therefore, the conventional
environmental equipment includes a denitrifier based on selective
catalytic reduction (SCR), which is placed after a flue gas
desulfurizer (FGD). The denitrifier based on the SCR needs to use a
burner for heating exhaust gas in order to raise the temperature of
the exhaust gas. Therefore, the conventional environmental
equipment has a problem in that operating costs are excessively
increased.
DISCLOSURE
Technical Problem
[0005] An aspect of the disclosure is to provide environmental
equipment, of which operating costs are significantly reduced, and
a power generation system including the same.
Technical Solution
[0006] To achieve the aspect of the disclosure, there is provided a
power generation system including: a boiler; an electric generator
which produces electricity based on steam generated in the boiler;
a first denitrifier which receives exhaust gas from the boiler and
denitrifies the exhaust gas by spraying a reductant to the exhaust
gas; a low low-temperature electric precipitator which collects
dust from the exhaust gas provided from the first denitrifier; a
second denitrifier which secondarily denitrifies the exhaust gas by
spraying the reductant to the exhaust gas provided from the low
low-temperature electric precipitator and provides the exhaust gas
toward a chimney; a first heat exchanger which is provided between
the first denitrifier and the low low-temperature electric
precipitator and cools the exhaust gas provided to the low
low-temperature electric precipitator; and a second heat exchanger
which is connected to the first heat exchanger between the low
low-temperature electric precipitator and the second denitrifier
and heats the exhaust gas provided to the second denitrifier.
[0007] The second denitrifier may secondarily denitrify the exhaust
gas based on a low temperature selective catalytic reduction
(SCR).
[0008] The first heat exchanger may cool the exhaust gas, to be
provided to the low low-temperature electric precipitator, to have
a temperature of 80.about.100 degrees, and the second heat
exchanger may heat the exhaust gas, to be provided to the second
denitrifier, to have a temperature of 150.about.200 degrees.
[0009] The power generation system may further include: a third
heat exchanger which is provided between the second denitrifier and
the chimney and cools the exhaust gas to be provided to the
chimney; and a fourth heat exchanger which is connected to the
third heat exchanger and heats air to be provided to the boiler and
used for combustion.
[0010] The power generation system may further include a catalyst
regenerator which is connected to at least one of the first
denitrifier and the second denitrifier and supplies a catalyst
regeneration material toward a catalyst in the denitrifier.
[0011] The catalyst regenerator may spray dry ice toward the
catalyst.
[0012] The catalyst regenerator may alternately spray dry ice and
hot steam toward the catalyst. p The catalyst regenerator may
include: a sprayer which is provided outside the denitrifier and
supplies the catalyst regeneration material from the outside, and a
spraying nozzle which is extended from the sprayer to an inside of
the denitrifier and moves up and down inside the denitrifier by a
motive power source to spray the catalyst regeneration material
toward the catalyst.
[0013] The catalyst regenerator may spray the catalyst regeneration
material to the catalyst when the catalyst is poisoned.
[0014] Meanwhile, environmental equipment connected to a boiler of
a power generation system according to the disclosure may include:
an electric generator which produces electricity based on steam
generated in the boiler; a first denitrifier which receives exhaust
gas from the boiler and denitrifies the exhaust gas by spraying a
reductant to the exhaust gas; a low low-temperature electric
precipitator which collects dust from the exhaust gas provided from
the first denitrifier; a second denitrifier which secondarily
denitrifies the exhaust gas by spraying the reductant to the
exhaust gas provided from the low low-temperature electric
precipitator and provides the exhaust gas toward a chimney; a first
heat exchanger which is provided between the first denitrifier and
the low low-temperature electric precipitator and cools the exhaust
gas provided to the low low-temperature electric precipitator; and
a second heat exchanger which is connected to the first heat
exchanger between the low low-temperature electric precipitator and
the second denitrifier and heats the exhaust gas provided to the
second denitrifier.
[0015] The second denitrifier may secondarily denitrify the exhaust
gas based on a low temperature SCR.
[0016] The first heat exchanger may cool the exhaust gas, to be
provided to the low low-temperature electric precipitator, to have
a temperature of 80.about.100 degrees, and the second heat
exchanger may heat the exhaust gas, to be provided to the second
denitrifier, to have a temperature of 150.about.200 degrees.
[0017] The power generation system may further include: a third
heat exchanger which is provided between the second denitrifier and
the chimney and cools the exhaust gas to be provided to the
chimney; and a fourth heat exchanger which is connected to the
third heat exchanger and heats air to be provided to the boiler and
used for combustion.
[0018] The power generation system may further include a catalyst
regenerator which is connected to at least one of the first
denitrifier and the second denitrifier and supplies a catalyst
regeneration material toward a catalyst in the denitrifier.
[0019] The catalyst regenerator may spray dry ice toward the
catalyst.
[0020] The catalyst regenerator may alternately spray dry ice and
hot steam toward the catalyst.
[0021] The catalyst regenerator may include: a sprayer which is
provided outside the denitrifier and supplies the catalyst
regeneration material from the outside, and a spraying nozzle which
is extended from the sprayer to an inside of the denitrifier and
moves up and down inside the denitrifier by a motive power source
to spray the catalyst regeneration material toward the
catalyst.
[0022] The catalyst regenerator may spray the catalyst regeneration
material to the catalyst when the catalyst is poisoned.
[0023] Meanwhile, a power generation system according to the
disclosure includes: a boiler; an electric generator which produces
electricity based on steam generated in the boiler; a low
low-temperature electric precipitator which receives exhaust gas
from the boiler and collects dust from the exhaust gas; a
denitrifier which denitrifies the exhaust gas by spraying the
reductant to the exhaust gas provided from the low low-temperature
electric precipitator and provides the exhaust gas toward a
chimney; a first heat exchanger which is provided between the
electric generator and the low low-temperature electric
precipitator and cools the exhaust gas provided to the low
low-temperature electric precipitator; and a second heat exchanger
which is connected to the first heat exchanger between the low
low-temperature electric precipitator and the denitrifier and heats
the exhaust gas provided to the denitrifier.
[0024] Meanwhile, environmental equipment connected to a boiler of
a power generation system according to the disclosure includes: an
electric generator which produces electricity based on steam
generated in the boiler; a low low-temperature electric
precipitator which receives exhaust gas from the boiler and
collects dust from the exhaust gas; a denitrifier which denitrifies
the exhaust gas by spraying the reductant to the exhaust gas
provided from the low low-temperature electric precipitator and
provides the exhaust gas toward a chimney; a first heat exchanger
which is provided between the electric generator and the low
low-temperature electric precipitator and cools the exhaust gas
provided to the low low-temperature electric precipitator; and a
second heat exchanger which is connected to the first heat
exchanger between the low low-temperature electric precipitator and
the denitrifier and heats the exhaust gas provided to the
denitrifier.
Advantageous Effects
[0025] Environmental equipment according to the disclosure and a
power generation system including the same, in which exhaust gas is
heated based on waste heat of the exhaust gas without a burner,
have effects on reducing operating costs and facilitating easy
installation and operation of the system.
[0026] The technical effects of the disclosure are not limited to
the foregoing effects, and other technical effects will become
apparent to those skilled in the art through the following
descriptions.
DESCRIPTION OF DRAWINGS
[0027] FIG. 1 is a conceptual view schematically illustrating a
power generation system according to an embodiment of the
disclosure,
[0028] FIG. 2 is a conceptual view illustrating automatic
catalyst-regeneration equipment in the power generation system
according to an embodiment of the disclosure, and
[0029] FIG. 3 is a flowchart showing operations of environmental
equipment according to an embodiment of the disclosure.
MODE FOR CARRYING OUT DISCLOSURE
[0030] Below, embodiments of the disclosure will be described with
reference to the accompanying drawings. However, the embodiments
are not limited to embodiments set forth herein, but may be
variously given to complete the disclosure and help a person having
ordinary knowledge in the art to fully understand the scope of the
disclosure. The shapes, etc. of elements in the accompanying
drawings may be exaggerated for clearer description, and like
numerals refer to like elements throughout the accompanying
drawings.
[0031] FIG. 1 is a conceptual view schematically illustrating a
power generation system according to an embodiment of the
disclosure, and FIG. 2 is a conceptual view illustrating automatic
catalyst-regeneration equipment in the power generation system
according to an embodiment of the disclosure.
[0032] As shown in FIGS. 1 and 2, a power generation system 1000
according to an embodiment of the disclosure includes a boiler 100,
environmental equipment 200, and a chimney 300.
[0033] First, the boiler 100 includes a combustion space in which a
burner is installed. In the boiler 100, fuel is supplied to the
burner, and air flows into the combustion space. Thus, the boiler
100 generates steam with thermal energy in the combustion space. In
this case, the fuel supplied to the boiler 100 may include fossil
fuel such as pulverized coal or heavy oil.
[0034] For example, when pulverized coal is used as fossil fuel,
the burner is provided as a pulverized-coal burner to spray air and
pulverized coal into the combustion space. In this case, the
pulverized-coal burner may include a low NOx burner to which a low
NOx (nitrogen oxide) combustion process is applied. However, the
low NOx burner is merely to describe an embodiment of the
disclosure, and various kinds of burners may be used. Further,
power generation equipment (not shown) is connected to the boiler
and produces electricity based on steam provided by the boiler
100.
[0035] Meanwhile, the environmental equipment 200 may include a
first denitrifier 210, a first rotary air-preheater 220, an
electric precipitator 230, a desulfurizer 240, a second denitrifier
250, and a catalyst regenerator 260. In this case, the
environmental equipment 200 is connected to the boiler 100 and
forms a course to discharge exhaust gas, from which pollutants are
removed, to the atmosphere through the chimney 300.
[0036] First, the first denitrifier 210 is placed between the
boiler 100 and the first rotary air-preheater 220 and receives
exhaust gas from the boiler 100. In this case, the first
denitrifier 210 may receive the exhaust gas which is primarily
denitrified by a selective non-catalytic reduction (SNCR) device or
NOx burner installed in the boiler 100. Thus, the first denitrifier
210 secondarily denitrifies the exhaust gas received from the
boiler 100.
[0037] Here, the first denitrifier 210 may include selective
catalytic reduction (SCR) device. Thus, the first denitrifier 210
sprays ammonia, urea or the like reductant to the exhaust gas,
thereby converting nitrogen oxide into nonpolluting water and
nitrogen on the catalyst.
[0038] Meanwhile, the first rotary air-preheater (or gas air
heater, GAH) is placed between the first denitrifier 210 and the
electric precipitator 230. Thus, the first rotary air-preheater 220
recovers waste heat from the exhaust gas provided by the
denitrifier. Further, the first rotary air-preheater 220 previously
heats air flowing into the combustion space, thereby improving a
combustion efficiency of the boiler 100. In other words, the first
rotary air-preheater 220 heats air supplied into the boiler 100 and
used for combustion with remaining heat previously used for the
combustion.
[0039] Further, the electric precipitator 230 is provided as a low
low-temperature electric precipitator between the first rotary
air-preheater 220 and the desulfurizer 240 and collects dust from
the exhaust gas provided by the first rotary air-preheater 220.
Here, the electric precipitator 230 may be provided as a dust
collector based on electrostatic separation. Thus, dust in the
exhaust gas is charged by a metal wire of a cathode, and the
charged dust is adhered to an anode shaped like a plate or
tube.
[0040] The electric precipitator 230 is suitable for large-scale
exhaust gas treatment and may additionally include a bag filter to
improve a dust-collection efficiency by a hybrid manner. However,
this is merely for describing an embodiment of the disclosure, and
does not limit the kinds of dust collectors.
[0041] Meanwhile, the desulfurizer 240 is provided between the
electric precipitator 230 and the second denitrifier 250 and
desulfurizes the exhaust gas provided by the electric precipitator
230. Here, the desulfurizer 240 may internally include a cyclone
for gas/liquid contact enhancement to improve a desulfurization
efficiency. Further, the desulfurizer 240 may be enlarged as
compared with a conventional one and additionally include a
plurality of gypsum sludge spraying nozzles or the like to keep a
desulfurization efficiency of 98% or higher. Further, the
desulfurizer 240 may include a mist eliminator in an inside upper
portion thereof to prevent gypsum slurry from spilling out. Thus,
sulfur dioxide of the exhaust gas is neutralized by reaction with
limestone in the desulfurizer 240 and changed into gypsum. In this
case, the gypsum may be recycled for industrial use.
[0042] Meanwhile, the second denitrifier 250 is provided between
the desulfurizer 240 and the chimney 300 and receives the exhaust
gas from the desulfurizer 240. In this case, the second denitrifier
250 may include a low-temperature SCR device. Thus, the second
denitrifier 250 denitrifies the exhaust gas provided by the
desulfurizer 240 so that the denitrified exhaust gas can be
discharged to the atmosphere through the chimney 300.
[0043] Meanwhile, a first heat exchanger 11 is provided between the
first rotary air-preheater 220 and the electric precipitator 230.
The first heat exchanger 11 is connected to a second heat exchanger
12 provided between the desulfurizer 240 and the second denitrifier
250. Here, the first heat exchanger 11 and the second heat
exchanger 12 may be embodied by tube-type gas gas heaters (GGH).
The first heat exchanger 11 cools the exhaust gas, and the second
heat exchanger 12 heats the exhaust gas. Further, a third heat
exchanger 13 is provided between the second denitrifier 250 and the
chimney 300. The third heat exchanger 13 is connected to a fourth
heat exchanger 14 provided on a course where air for combustion
flows into the first rotary air-preheater 220. Here, the third heat
exchanger 13 may be provided as an air preheater that recovers
waste heat from the exhaust gas, and thus air to be supplied to the
boiler 100 and used for combustion is heated by the fourth heat
exchanger 14. The third heat exchanger 13 and the fourth heat
exchanger 14 may be embodied by rotary or tubular heat
exchangers.
[0044] Further, the catalyst regenerator 260 may be connected to at
least one of the first denitrifier 210 and the second denitrifier
250. The catalyst regenerator 260 sprays catalyst regeneration
materials to catalysts 211 and 251 when the catalysts 211 and 251
are poisoned during the operations of the denitrifiers, thereby
preventing the life of the catalysts 211 and 251 from being
shortened. In this case, the catalyst regenerator 260 may spray the
catalyst regeneration materials including dry ice to the
catalysts.
[0045] The catalyst regenerator 260 may include a
catalyst-regeneration material feeder 261, a sprayer 262, and a
spraying nozzle 263. The catalyst-regeneration material feeder 261
may be placed outside the denitrifier and feed the catalyst
regeneration material such as dry ice pellet into the sprayer 262.
Further, the sprayer 262 sprays the catalyst regeneration material
to the catalysts 211 and 251. To this end, the sprayer 262 is
connected to the spraying nozzle 263 neighboring on the catalysts
211 and 251 outside the denitrifiers and supplies the catalyst
regeneration material to the spraying nozzle 263. Here, the
spraying nozzle 263 includes a single spraying hole or a plurality
of spraying holes to uniformly spray the catalyst regeneration
material to the entire surfaces of the catalysts 211 and 251. The
spraying nozzle 263 may be connected to a motor, an actuator or the
like motive power source, and move up and down inside the
denitrifier.
[0046] Thus, the catalyst regenerator 260 has an advantage of
preventing the catalyst from being poisoned and shortened in
life.
[0047] The catalyst regenerator 260 in an embodiment of the
disclosure is connected to at least one of the first denitrifier
210 and the second denitrifier 250. However, the catalyst
regenerator 260 may be installed only in the second denitrifier
250, and may be installed in both the first denitrifier 210 and the
second denitrifier 250 when coal quality is bad.
[0048] In an embodiment of the disclosure, the catalyst regenerator
260 sprays dry ice. However, this is merely for describing an
embodiment of the disclosure, and the catalyst regenerator may
alternately spray dry ice and hot steam.
[0049] Further, the environmental equipment 200 according to an
embodiment of the disclosure includes the first denitrifier 210 and
the second denitrifier 250. However, this is merely for describing
an embodiment of the disclosure, and the environmental equipment
200 may include only the second denitrifier 250 without the first
denitrifier 210 as necessary.
[0050] Below, operations of the environmental equipment according
to an embodiment of the disclosure will be described in detail.
Here, repetitive descriptions to the foregoing elements will be
avoided, and like numerals refer to like elements.
[0051] FIG. 3 is a flowchart showing operations of environmental
equipment according to an embodiment of the disclosure.
[0052] As shown in FIG. 3, the environmental equipment 200
according to an embodiment of the disclosure removes pollutants
from exhaust gas provided by the boiler 100 and discharges the
exhaust gas to the atmosphere through the chimney 300.
[0053] First, the exhaust gas discharged from the boiler 100 is
primarily denitrified in the first denitrifier 210 (S100). In this
case, the first denitrifier 210 sprays a reductant to the exhaust
gas so that nitrogen oxide can be converted into water and
nitrogen.
[0054] Further, the exhaust gas discharged from the first
denitrifier 210 is provided to the first rotary air-preheater 220.
In this case, the exhaust gas provided to the first rotary
air-preheater 220 has a temperature of about 360 degrees. Here, the
first rotary air-preheater 220 recovers waste heat from the exhaust
gas and heats air, which will be provided to the boiler 100 and
used for combustion, with the waste heat.
[0055] Then, the exhaust gas is supplied from the first rotary
air-preheater 220 to the electric precipitator 230 via the first
heat exchanger 11. In this case, the exhaust gas having a
temperature of about 180.about.250 degrees is provided to the first
heat exchanger 11, and the first heat exchanger 11 recovers heat
from the exhaust gas so that the exhaust gas having a temperature
of about 90 degrees, for example, 80.about.100 degrees can be
provided to the electric precipitator 230.
[0056] Then, the electric precipitator 230 collects dust from the
exhaust gas (S200). The exhaust gas, from which dust has been
removed, is provided to the desulfurizer 240. In this case, the
exhaust gas provided to the desulfurizer 240 may be maintained at a
temperature of about 90.
[0057] Further, the desulfurizer 240 desulfurizes the exhaust gas
(S300). Thus, sulfur dioxide of the exhaust gas is neutralized by
reaction with limestone and changed into gypsum, and the
desulfurizer 240 supplies the desulfurized exhaust gas to the
second denitrifier 250. In this case, the exhaust gas passed
through the desulfurizer 240 may have a temperature of about 50
degrees.
[0058] Meanwhile, the second heat exchanger 12 placed between the
desulfurizer 240 and the second denitrifier 250 heats the exhaust
gas provided by the desulfurizer 240 so that the exhaust gas having
a temperature of about 150.about.200 degrees can be provided to the
second denitrifier 250. Here, the second heat exchanger 12 does not
need a burner because the waste heat of the exhaust gas is recycled
to heat the exhaust gas. Thus, the environmental equipment 200
excludes or does not employ the burner, thereby reducing fuel costs
by more than 10 billion won per year in the case of a 500 MW-class
coal-fired power station.
[0059] Meanwhile, the second denitrifier 250 secondarily
denitrifies the exhaust gas (S400). Here, the second denitrifier
250 secondarily denitrifies the exhaust gas based on
low-temperature SCR, so that the secondarily denitrified exhaust
gas can be provided toward the chimney 300. Here, the exhaust gas
may have a temperature of about 150.about.200 degrees.
[0060] Meanwhile, the third heat exchanger 13 recovers waste heat
from the exhaust gas provided toward the chimney, and thus the
exhaust gas having a temperature of about 60.about.85 degrees is
discharged through the chimney 300. In this case, the fourth heat
exchanger 14 additionally raises the temperature of air, which will
be provided to the first rotary air-preheater 220 and used for
combustion, by 25 degrees or higher, based on the waste heat
recovered in the third heat exchanger 13. Thus, the environmental
equipment 200 improves the efficiency of the boiler by about 1% or
more, and has an effect on reducing costs by 3.3 billion won per
year in the case of the 500 MW-class coal-fired power station.
[0061] Accordingly, the environmental equipment according to the
disclosure and the power generation system including the same have
effect on reducing operating costs and facilitating easy
installation and operation of the system because the exhaust gas is
heated based on the waste heat of the exhaust gas without the
burner.
[0062] The embodiments of the disclosure described above and
illustrated in the accompanying drawings should not be construed as
limiting the technical idea of the disclosure. The scope of the
disclosure is limited only by matters disclosed in the appended
claims, and various improvements and changes can be made by a
person having ordinary knowledge in the art without departing from
the technical idea of the disclosure. Therefore, such improvements
and changes fall within the scope of the disclosure as long as they
are apparent to those skilled in the art.
* * * * *